In the manufacture of various products, such as case goods in the furniture industry, it is often desirable to incorporate one or more premanufactured wooden panels in the design of the product. These panels can be made from a monolithic piece of wood or can be built up from certain discrete layers or plies of wood. Another successful approach to forming wood panels involves adhering together a collection of boards having a rectangular cross-section in an edge-to-edge configuration. For example, wooden boards having a thickness of one inch and a width of two inches can be adhered together along their narrower edges to create a panel such as the top of a kitchen table. Another example of panel made from wood pieces is a raised panel of a cabinet door.
Various apparatus have been proposed for automatically creating panels made from adhered wood pieces. For example, U.S. Pat. No. 5,240,051 discloses a dual automated clamp carrier for gluing together panels of wood from wood panel segments. The machine includes a plurality of clamp racks in which panels are clamped so that the individual panel segments can be glued together. For example, as noted in connection with the embodiment of FIG. 11, the panels are assembled manually by an operator who first must lift a completed panel from a clamp rack and then stack new panel segments into the clamps on the clamp rack to layout a new panel. (Col. 8, lines 39-41). However, a disadvantage of this approach is that the panels must first be assembled by an operator, which undesirably involves manual labor costs and the risk that the operation will become messy because the operator must handle boards having a wet adhesive applied thereto. In addition, the apparatus can only create panels of limited width (as determined by the spacing of the clamps) and does not provide for the continuous manufacture of wood paneling material.
An improvement on this conventional apparatus is embodied in a continuous gluer machine available from Radio Frequency Services, Inc. in Wilkesboro, N.C. In particular, the model CG/RF includes an infeed system for a press that allows continuous production of wooden panels. Wood pieces are supplied from the infeed system with an adhesive applied to a leading edge of the wood piece. Within the press, the leading edge of a wood piece is pressed against the trailing edge of the immediately preceding wood piece. The immediately preceding wood piece is securely clamped and held stationary while the subsequent wood piece with the adhesive applied thereto is pressed against the preceding wood piece. The adhesive is then cured to form a secure bond. Advantageously, the adhesive is curable by way of a radio frequency energy field and the apparatus includes a radio frequency generator as part of the press, which rapidly and securely cures the adhesive between the wood pieces. Thus, the model CG/RF allows the production of a “continuous ribbon” of wood panel material comprising a series of wood pieces adhered together at their edges.
While the model CG/RF has provided great advantages over conventional apparatus, the infeed system requires that the individual wood pieces be moved transversely to the machine direction when applying the adhesive to the edges of the wood pieces. An adhesive extruder is provided adjacent the main conveyor and each wood piece is fed laterally to the conveyor such that a leading edge of the wooden piece is passed along the adhesive extruder and adhesive is applied thereto. However, in the model CG/RF, wood pieces are supplied to the conveyor in a transverse direction, which can consume potentially valuable floor space adjacent the side of the conveyor. In addition, as would be appreciated by one of ordinary skill in the art, the adhesive application process is dependent on the length of the wood piece in question, which might not provide sufficient line speed.
Another limitation on conventional apparatus relates to subsequent cutting of the wood panels to a desired size. For example, conventional cutting apparatus include a saw capable of cutting in a cross-machine direction to create panels of a predetermined width from the continuous ribbon of wood panel material as the material exits the press. However, in machines that make a single ribbon of wood paneling material, these saws are not capable of easily and quickly being adjusted to cut off panels of varying widths. The ability to cut panels of different predetermined widths at an acceptable manufacturing speed would be highly desirable.
Thus, there is a need in the industry for an apparatus and method that provide continuous production of wooden panels from a series of adhered wood pieces. Such an apparatus would not only allow continuous manufacture of these panels, but would also eliminate the need to supply wood pieces transversely to the main conveyor and would provide automatic application of the adhesive to the edges of the wood pieces. In addition, such an apparatus would also preferably be capable of cutting off panels from the continuous panel material that have different predetermined widths, and would do so at manufacturing speeds.